JSI Tip 10583. Exchange services do not start, and event IDs 2114 and 2112 are logged in the Application log in Exchange Server 2003 or in Exchange 2000 Server?

Microsoft Knowledge Base Article 919089 contains the following summary:

This article describes a problem that may occur when the Directory Service Access (DSAccess) component cannot communicate with the Active Directory directory service. To resolve this problem, you must verify the following:

•	The default domain policy or the default domain controllers policy is not blocked by a "No override" configuration on an organizational unit object or on the domain object.
•	The Manage Auditing Security Privilege user right in the default domain controllers policy is applied to the Exchange Enterprise Servers group.
•	The computer account of the affected Exchange server is included in the Exchange Domain Servers group.